Cytosolic viral sensor RIG-I is a 5′-triphosphate-dependent translocase on double-stranded RNA

Sua Myong, Sheng Cui, Peter V. Cornish, Axel Kirchhofer, Michaela U. Gack, Jae U. Jung, Karl Peter Hopfner, Taekjip Ha

Research output: Contribution to journalArticlepeer-review


Retinoic acid inducible-gene I (RIG-I) is a cytosolic multidomain protein that detects viral RNA and elicits an antiviral immune response. Two N-terminal caspase activation and recruitment domains (CARDs) transmit the signal, and the regulatory domain prevents signaling in the absence of viral RNA. 5′-triphosphate and double-stranded RNA (dsRNA) are two molecular patterns that enable RIG-I to discriminate pathogenic from self-RNA. However, the function of the DExH box helicase domain that is also required for activity is less clear. Using single-molecule protein-induced fluorescence enhancement, we discovered a robust adenosine 5′-triphosphate-powered dsRNA translocation activity of RIG-I. The CARDs dramatically suppress translocation in the absence of 5′-triphosphate, and the activation by 5′-triphosphate triggers RIG-I to translocate preferentially on dsRNA in cis. This functional integration of two RNA molecular patterns may provide a means to specifically sense and counteract replicating viruses.

Original languageEnglish (US)
Pages (from-to)1070-1074
Number of pages5
Issue number5917
StatePublished - Feb 20 2009

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Cytosolic viral sensor RIG-I is a 5′-triphosphate-dependent translocase on double-stranded RNA'. Together they form a unique fingerprint.

Cite this